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DF : Cyberpunk 2077 - How is path tracing possible

Buggy Loop

Member


A superb analysis from Alex and a master class of the tech behind Cyberpunk overdrive. I made many posts in the past related to ReSTIR but there's nothing like a visual medium like a video to go through tech.

Going from Quake 2 RTX in 2019 to Cyberpunk 2077 overdrive in just 4 years is a mind bending tech tour de force.

DF is the first i've seen that goes into ReSTIR's tech outside of the published papers.
  • Every Nvidia gen keeps doubling the ray/triangle intersection rate
    • Turing 1x ray/triangle intersection rate
    • Ampere 2x ray/triangle intersection rate
    • Ada 4x ray/triangle intersection rate
  • Path tracing's randomness is heavy on SIMD (simultaneous instruction/mutiple data)
    • L2 cache increase useful core utilisation
      • RTX 4090 72 MB
      • RTX 3090 6 MB
      • RX 6900 XT 4 MB
      • RX 7900 XTX 6 MB
    • SER (Shader execution reordering), exclusive to Ada. This again helps with the SIMD inefficiencies with path tracing's randomness. It reorders the data to group a set of similar tasks in one group. Say all mirror like surfaces together, rough surfaces in another group, etc. A game like CP2077 has a huge variety of shaders for different materials. Path tracing being physically accurate with the bounces, they hit the shaders in a haphazard way and SER reorganizes that mess.
  • ReSTIR - This is the biggest unlock for making it possible in cyberpunk 2077.
    • ReSTIR/RTXDI has virtually unlimited number of lights.
    • The brute force "monte carlo" path tracing of Quake 2 RTX would maybe have tens of light sources, Cyberpunk 2077 might have hundreds in a given scene. The old method would require many rays to get a result that the denoising can actually clean the image. ReSTIR wipes the floor with old path tracing for the resulting image quality with so many lights. The Quake 2 RTX method would not be possible for Cyberpunk 2077.
    • Much easier to denoise
  • Image reconstruction (duh) DLSS 2 / DLSS 3 frame gen.
  • Future upcoming tech :
    • It lacks path tracing for transparent objects (shocked pikachu). It's a tech preview and likely to be added.
    • NRC is Nvidia's next caching technology that will also solve the above problem and is even faster and less noisy than ReSTIR.
    • OMM - Pacity micro-map : An asset format that can be read by Ada lovelace only, which speeds up the tracing of alpha tested geometry
 
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mansoor1980

Gold Member
even_possible_aliens.gif
 

Zathalus

Member
Damn, the 4090 is like 4.5 times as powerful as the 2080ti in path tracing, and that's without SER. Good improvement on the RT front for Nvidia gen on gen.
 

01011001

Banned
Isn't quake 2 fully path traced and cyberpunk only lighting.

lighting is realistically the only thing you have to trace.

given that the final image in a game is almost always a bunch of textures that are lit by the raytraced lighting, you could say that 99.9% of the pixels drawn while playing Cyberpunk's RT overdrive mode are colored due to the result of raytracing and the denoising applied to it, which is practically speaking nearly the same as Quake 2
 
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LiquidMetal14

hide your water-based mammals
A testament and great to see graphics advancing to this with us on PC at the forefront of stuff like this.

You gotta love when new stuff like this comes out like the advent of 3D graphics. Reiterating that this is a great time for the advancement of graphics and generally the tech driving these new frontiers in terms of what we can do in real time today on PC.
 

TrueLegend

Member
The shilling for Nvidia continues which praising of demos. Tech demos, this mode n that mode meanwhile all games launch broken despite dlss n fsr 2.1 present. DF is jerking nvidias dick off unashamed with three videos on this one update. Meanwhile when games launch broken 'I wonder what has caused this, suddenly all our intelligence is gone'. Name one time they have bashed game Devs. Game Devs can't do no wrong. Nvidia can do no wrong but hey love us as we single handly become nvidias puppet in planned obsolence. Also we hate console wars but we actively title our videos as versus become you know the word 'and' doesn't exist.
 
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Gaiff

SBI’s Resident Gaslighter
The shilling for Nvidia continues which praising of demos. Tech demos, this mode n that mode meanwhile all games launch broken despite dlss n far 2.1 present. DF is jerking nvidias dick off unashamed with three videos on this one update. Meanwhile when games launch broken 'I wonder what has caused this, suddenly all our intelligence is gone'. Name one time they have bashed game Devs. Game Devs can't do no wrong. Nvidia can do no wrong but hey love us as we single handly become nvidias puppet in planned obsolence. Also we hate console wars but we actively title our videos as versus become you know the word 'and' doesn't exist.
spiderman-thats-it.gif
 

Turk1993

GAFs #1 source for car graphic comparisons
The shilling for Nvidia continues which praising of demos. Tech demos, this mode n that mode meanwhile all games launch broken despite dlss n far 2.1 present. DF is jerking nvidias dick off unashamed with three videos on this one update. Meanwhile when games launch broken 'I wonder what has caused this, suddenly all our intelligence is gone'. Name one time they have bashed game Devs. Game Devs can't do no wrong. Nvidia can do no wrong but hey love us as we single handly become nvidias puppet in planned obsolence. Also we hate console wars but we actively title our videos as versus become you know the word 'and' doesn't exist.
So praising the most advanced GPU and graphically most advanced game ever is now called shilling lol. Foh with that bullshit, without Nvidia we would be still playing last gen looking games.
 

Buggy Loop

Member
The shilling for Nvidia continues which praising of demos. Tech demos, this mode n that mode meanwhile all games launch broken despite dlss n far 2.1 present. DF is jerking nvidias dick off unashamed with three videos on this one update. Meanwhile when games launch broken 'I wonder what has caused this, suddenly all our intelligence is gone'. Name one time they have bashed game Devs. Game Devs can't do no wrong. Nvidia can do no wrong but hey love us as we single handly become nvidias puppet in planned obsolence. Also we hate console wars but we actively title our videos as versus become you know the word 'and' doesn't exist.

Where did DF touch you?

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They've called out shitty ports time and time again, actually mostly OPPOSITE of 99% of the fucking praising reviews from the mainstream media who scores shit 10/10 and then you realize its an unplayable mess.

Cyberpunk 2077 is literally something that shouldn't exist just 4 years after the likes of Quake 2 RTX & Minecraft RTX demos. Hell, Portal RTX not even long ago was bringing most rigs to their knees. 3 videos for this tech mind bending achievement is not even enough. The entire industry for path tracing technology was shaken by their ReSTIR papers, not just "GPU" tech, universities & scholars all refer Nvidia's ReSTIR papers nowadays to try to find the next improvement.
 
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Senua

Gold Member
The shilling for Nvidia continues which praising of demos. Tech demos, this mode n that mode meanwhile all games launch broken despite dlss n far 2.1 present. DF is jerking nvidias dick off unashamed with three videos on this one update. Meanwhile when games launch broken 'I wonder what has caused this, suddenly all our intelligence is gone'. Name one time they have bashed game Devs. Game Devs can't do no wrong. Nvidia can do no wrong but hey love us as we single handly become nvidias puppet in planned obsolence. Also we hate console wars but we actively title our videos as versus become you know the word 'and' doesn't exist.

200.gif
 

Turk1993

GAFs #1 source for car graphic comparisons
excuse me?
What about Metro Exodus enhanced edition?
Full rt. Even 1800p60 on consoles.
Its not the same, Cyberpunk uses path tracing for its lighting which is more advanced than ray tracing for lighting. Also Cyberpunk has the full RT pack with PT lighting on top of it. Its technially the most advanced game ever released. Some scenes in Cyberpunk have 1000's of lights that have bounce lighting and create individual accurate shadows.
 

rofif

Can’t Git Gud
Not comparable with Pathtracing.
Not path tracing

See one of my previous post : DDGI/RTXGI

It was a good advancement but nowhere close to the complexity of path tracing.
Same thing really.
You got light dots, bounces and all that GI stuff. It's not just a screen shader.
It's way more expensive and a bit more precise for what I can tell. But Metro Exodus lighting is already very realistic. I wonder how it would look with full path tracing then
 

GHG

Member
The shilling for Nvidia continues which praising of demos. Tech demos, this mode n that mode meanwhile all games launch broken despite dlss n far 2.1 present. DF is jerking nvidias dick off unashamed with three videos on this one update. Meanwhile when games launch broken 'I wonder what has caused this, suddenly all our intelligence is gone'. Name one time they have bashed game Devs. Game Devs can't do no wrong. Nvidia can do no wrong but hey love us as we single handly become nvidias puppet in planned obsolence. Also we hate console wars but we actively title our videos as versus become you know the word 'and' doesn't exist.

No need for tears my friend.

nvidia-jensen-huang.gif
 

CGNoire

Member
The shilling for Nvidia continues which praising of demos. Tech demos, this mode n that mode meanwhile all games launch broken despite dlss n far 2.1 present. DF is jerking nvidias dick off unashamed with three videos on this one update. Meanwhile when games launch broken 'I wonder what has caused this, suddenly all our intelligence is gone'. Name one time they have bashed game Devs. Game Devs can't do no wrong. Nvidia can do no wrong but hey love us as we single handly become nvidias puppet in planned obsolence. Also we hate console wars but we actively title our videos as versus become you know the word 'and' doesn't exist.
Listen I hear you on DF and I personally think they have fallen pretty far ever since they started posting weekly videos with those Derp Face Thumnails for clicks. But this aint it.

Just 4 years ago pathtracing was only doeable on a game made in 98. Just 6 months ago it was only doeable on a small indie sized game (Portal) which was released in 2007. Not only have they achieved this working on a AAA PS4 game released in 2018 but have actually achieved higher framerates than with Portal and thats native before you apply DLSS on it. For a tech review platform to ignore such a breakthrough or for them to not do super detailed "time consuming" and yes even multiple video consuming breakdowns would make no sense. This wont be the last Overdrive video and it shouldnt be.
 

Buggy Loop

Member
Same thing really.
You got light dots, bounces and all that GI stuff. It's not just a screen shader.
It's way more expensive and a bit more precise for what I can tell. But Metro Exodus lighting is already very realistic. I wonder how it would look with full path tracing then

Same limits as the previous Cyberpunk ray tracing mode (RTXGI). That's why cyberpunk 2077 ray tracing psycho vs path tracing comparisons are quite fit for what it could be with metro exodus. Metro Exodus also doesn't have many light sources being this kind of apocalyptic world compared to a city.

Everything is a matter of accuracy with lighting. From ray tracing which is not physically accurate to physically accurate path tracing, there's a world of computational requirement difference between them.

Look back at the DF analysis of Metro Exodus EE. For the time it was really good but it still had that screen space reflection effect inherent problems where the reflections should revert back to rasterization as you angled the world's geometry a certain way with the camera.
 

CGNoire

Member
Same thing really.
You got light dots, bounces and all that GI stuff. It's not just a screen shader.
It's way more expensive and a bit more precise for what I can tell. But Metro Exodus lighting is already very realistic. I wonder how it would look with full path tracing then
I think with PT its a unified process where for instance here AO isnt being fudged or calculated serperatly but is an actual sideeffect of the overall lighting process just like shadows in real life not being actually projected but being the result of a lack of lighting.
 

SlimySnake

Flashless at the Golden Globes
Listen I hear you on DF and I personally think they have fallen pretty far ever since they started posting weekly videos with those Derp Face Thumnails for clicks. But this aint it.

Just 4 years ago pathtracing was only doeable on a game made in 98. Just 6 months ago it was only doeable on a small indie sized game (Portal) which was released in 2007. Not only have they achieved this working on a AAA PS4 game released in 2018 but have actually achieved higher framerates than with Portal and thats native before you apply DLSS on it. For a tech review platform to ignore such a breakthrough or for them to not do super detailed "time consuming" and yes even multiple video consuming breakdowns would make no sense. This wont be the last Overdrive video and it shouldnt be.
TrueLegend is what happens when you go full truther. i like me some DF bashing every now and then but this is a great video, and what Alex is actually good at. And this path tracing shit is serious insanity considering im able to play this on my 30 series card.

P.S DF has been bashing devs for months now over bad PC ports. He was even made fun of here on gaf when he made his Top 10 ways to fix PC ports video. Gaf is ridiculous sometimes. When the guy bashes devs, he is criticized. When he praises them, hes criticized. Like come on. Make up your mind.
 

Senua

Gold Member
TrueLegend is what happens when you go full truther. i like me some DF bashing every now and then but this is a great video, and what Alex is actually good at. And this path tracing shit is serious insanity considering im able to play this on my 30 series card.

P.S DF has been bashing devs for months now over bad PC ports. He was even made fun of here on gaf when he made his Top 10 ways to fix PC ports video. Gaf is ridiculous sometimes. When the guy bashes devs, he is criticized. When he praises them, hes criticized. Like come on. Make up your mind.
Gaf is just pessimistic as fuck

Half of that Unrecord thread was negative, where practically everywhere else on the net was 100% positive
 
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Buggy Loop

Member
TrueLegend is what happens when you go full truther. i like me some DF bashing every now and then but this is a great video, and what Alex is actually good at. And this path tracing shit is serious insanity considering im able to play this on my 30 series card.

P.S DF has been bashing devs for months now over bad PC ports. He was even made fun of here on gaf when he made his Top 10 ways to fix PC ports video. Gaf is ridiculous sometimes. When the guy bashes devs, he is criticized. When he praises them, hes criticized. Like come on. Make up your mind.

Morgan Freeman Reaction GIF by MOODMAN


It’s getting tiring to see the bashing for DF and Alex in particular.
 

SlimySnake

Flashless at the Golden Globes
Gaf is just pessimistic as fuck

Half of that Unrecord thread was negative, where practically everywhere else on the net was 100% positive
Pessimism is fine. In the case of Unrecord which looks literally photorealistic, its fair to be a bit skeptical. Especially considering the fact that major first and third party devs have not even come close to match those visuals and this one dude made an entire level in a span of 6 months. Is the entire industry sleeping at the wheel or is this guy Jesus himself?
 

Buggy Loop

Member
Whats path tracing actually? How does it differ from earlier raytracing techniques?

One of my older post

This confuses a whole bunch of peoples on the internet because there's a mismatch papers/offline rendering/games. Even one of DICE's ex engine engineer who has a series on youtube was getting a headache from all the different interpretations.

TLDR for gaming : Path tracing is physically accurate ray bounces while ray tracing is always with a hack/approximation. The bounce in RTXGI/DDGI games (ray tracing) is more often than not a random direction based on material and then goes directly to probe.

Path tracing is really the rays out of camera → hitting objects kind of setup. All DDGI/RTXGI solutions have been probe-grids based solutions (ala rasterization). It's good, and its a step up from just rasterization, but also has limits and is still more complex to setup and can have the same light leaks problems as rasterization if devs aren't looking for the solution everywhere.

As seen here :



So it's valid of highly static scenes and are still touch up by artists to correct the volumes.

Path tracing is..

 
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Pedro Motta

Member
lighting is realistically the only thing you have to trace.

given that the final image in a game is almost always a bunch of textures that are lit by the raytraced lighting, you could say that 99.9% of the pixels drawn while playing Cyberpunk's RT overdrive mode are colored due to the result of raytracing and the denoising applied to it, which is practically speaking nearly the same as Quake 2
This is wrong.

Lighting is one of the things that can be path traced, but also shaders, and this is lacking in CP overdrive mode.

With path traced shaders you could have realistic refractions, Sub surface scattering, caustics, realistic fur depth shadow maps, realistic absoption and scattering of glossy materials, dispersion etc.

We're still long ways from full path tracing, but getting closer by the year.
 

CGNoire

Member
Morgan Freeman Reaction GIF by MOODMAN


It’s getting tiring to see the bashing for DF and Alex in particular.
I have my issues with DF but hands down there coverage of CP ODM has been really good and this video in particular was vey well put together. They go back and forth with me. Sometimes I think they give devs a pass or purposely reword critiques in the most "dont bite the hand that feeds ya" kind of way.
 

CGNoire

Member
Gaf has made up its mind a long time ago; shit on DF for whatever stance they take. There's a reason industry professionals avoid this place like the plague. Even when NxGamer pops up every once in a while, he gets dogpiled and accused of every damn thing.
Seems better than what happens at era where if you critique DF in anyway you can get banned.
 

LiquidMetal14

hide your water-based mammals
TrueLegend is what happens when you go full truther. i like me some DF bashing every now and then but this is a great video, and what Alex is actually good at. And this path tracing shit is serious insanity considering im able to play this on my 30 series card.

P.S DF has been bashing devs for months now over bad PC ports. He was even made fun of here on gaf when he made his Top 10 ways to fix PC ports video. Gaf is ridiculous sometimes. When the guy bashes devs, he is criticized. When he praises them, hes criticized. Like come on. Make up your mind.
The son of bitch is right.
 

TrueLegend

Member
Morgan Freeman Reaction GIF by MOODMAN


It’s getting tiring to see the bashing for DF and Alex in particular.
He has never bashed Dev's....he says I don't know what happened but the performance is poor. Also half of the guy on steam could make better video on what we want from PC ports that will not be as stupid as his video which was more about make my workflow easier. And If DF bashing was that regular their video wouldn't be posted here all the time.

As far as Alex is considered, this son of a bitch didn't shame God of War Dev's when the AMD GPU performance was abyssmal for moths because he had an exclusive interview and I am not saying that because I had AMD GPU, I was perfectly fine with my 3070 at 4k60. He also was so lazy that he didn't play uncharted 4 properly otherwise he wouldn't have missed the abyssmal memory leak issue and wouldn't have been suprised for Last of Us bad performance. Arkham knight had bad texture streaming pool config, uncharted LOT had it and now TLOU has it. Do the math sherlok.....Iron Galaxy sucks at it. He is crying shader compilation now but he was very forgiving about it when control launched with shader compilation issues n horrible texture streaming bug that persists till date. Go watch his old video. He basically promotes Ray tracing over optimization, only now he is crying about it because even the flagship card is struggling too much with it.
 
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CGNoire

Member
Atleast I don't need to upgrade my GPU. You need to worry about your medication cuz you will soon be buying 5090.
But the problem is there is no real upgrade for High end PC enthusiasts in this decade of our lord 2020s that clearly surpasses consoles anymore.*

1.Where not getting higher res textures (at least not noticeably so)

2. Consoles already have high resolutions and pretty damm good image quality. (At least when standing still ...temporal issues aside.)

3. Most recent games have a 60fps mode for those that dont have a PC.
Some even have 120fps modes.

As far as Im concerned outside of Native resolutions which only really benefit those with high motion resolution displays and some higher AF settings I hate to say it but what do we high end Pc enthusiats get graphically for our investment right now?......basicly just RT sadly.

With that being said why shouldnt Nvida's unparelleled advancments not be celebrated?.......even if they are criminally overcharging.


*(outside of those that demand 120fps on everything)
 
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Turk1993

GAFs #1 source for car graphic comparisons
I am not a dumb bitch like you. If you used a little bit brain you would have found out I have multiple Nvidia GPU's including a 4080, a 3090 and 3070.

GHG GHG get off my proche. This shit is not true pathtracing. He didn't even talk about low sample count of shadow rays causing heavy noise and I mentioned ReSTIR way before him. He only mentioned caustics like other faults are not presents in ReSTIR. Oh right he will talk about it when he will shit on cyberpunk RT overdrive when Nvidia will launch 7090 with 5000usd MSRP...like every other iPhone reviewer...for ofc now it's perfect. But don't look at the soupyness n noise....because it's all perfect. Get off.
e89d3500cb5a1e45c075070d258c5d5d.gif


yP0hCDY.jpg
 

kingyala

Banned


A superb analysis from Alex and a master class of the tech behind Cyberpunk overdrive. I made many posts in the past related to ReSTIR but there's nothing like a visual medium like a video to go through tech.

Going from Quake 2 RTX in 2019 to Cyberpunk 2077 overdrive in just 4 years is a mind bending tech tour de force.

DF is the first i've seen that goes into ReSTIR's tech outside of the published papers.
  • Every Nvidia gen keeps doubling the ray/triangle intersection rate
    • Turing 1x ray/triangle intersection rate
    • Ampere 2x ray/triangle intersection rate
    • Ada 4x ray/triangle intersection rate
  • Path tracing's randomness is heavy on SIMD (simultaneous instruction/mutiple data)
    • L2 cache increase useful core utilisation
      • RTX 4090 72 MB
      • RTX 3090 6 MB
      • RX 6900 XT 4 MB
      • RX 7900 XTX 6 MB
    • SER (Shader execution reordering), exclusive to Ada. This again helps with the SIMD inefficiencies with path tracing's randomness. It reorders the data to group a set of similar tasks in one group. Say all mirror like surfaces together, rough surfaces in another group, etc. A game like CP2077 has a huge variety of shaders for different materials. Path tracing being physically accurate with the bounces, they hit the shaders in a haphazard way and SER reorganizes that mess.
  • ReSTIR - This is the biggest unlock for making it possible in cyberpunk 2077.
    • ReSTIR/RTXDI has virtually unlimited number of lights.
    • The brute force "monte carlo" path tracing of Quake 2 RTX would maybe have tens of light sources, Cyberpunk 2077 might have hundreds in a given scene. The old method would require many rays to get a result that the denoising can actually clean the image. ReSTIR wipes the floor with old path tracing for the resulting image quality with so many lights. The Quake 2 RTX method would not be possible for Cyberpunk 2077.
    • Much easier to denoise
  • Image reconstruction (duh) DLSS 2 / DLSS 3 frame gen.
  • Future upcoming tech :
    • It lacks path tracing for transparent objects (shocked pikachu). It's a tech preview and likely to be added.
    • NRC is Nvidia's next caching technology that will also solve the above problem and is even faster and less noisy than ReSTIR.
    • OMM - Pacity micro-map : An asset format that can be read by Ada lovelace only, which speeds up the tracing of alpha tested geometry

its not path tracing... why does alex always gets his tits up whenever some new pc technology pops up and starts his marketing videos... he chats like cyberpunk has finally discovered the holy grail of graphics.. when its all hybrid globa illumination tricks.. he sounds like some youtube get rich quick ad. sometimes!
 

Buggy Loop

Member
its not path tracing... why does alex always gets his tits up whenever some new pc technology pops up and starts his marketing videos... he chats like cyberpunk has finally discovered the holy grail of graphics.. when its all hybrid globa illumination tricks.. he sounds like some youtube get rich quick ad. sometimes!

Oh, we have that other guy who always says "this is not ray tracing" and now "this is not path tracing"!

WHOLE GODDAMN STUPID GANG IS IN!
 

Buggy Loop

Member
I hate being a party pooper but i also hate lying... and here is epic engineer debunking the validity of calling this path tracing...

KlPuW9O.jpg
jcOO7Ta.jpg

You quote someone but you still don't understand what you even read

Of course it's not a classic 80's Monte Carlo path tracing like the guy is "confused" about. It's BETTER. Whether you call it path tracing or not, who the fuck cares, that's a debate for scholars, but everyone is refering to Nvidia's solution on their papers as a path tracing solution.

gLq3lvE.jpg


Path tracing is a mean to get to a reference image. There's tons of twists and changes in algorithms since the Monte Carlo solution (which is slow as fuck even by optimization standards nowadays), so is ReSTIR DI + ReSTIR PT a solution towards reference image.

There's not a single pipeline in unreal engine where you're rid of the rasterization either, nor their path tracing plugin. So should epic remove the word path tracing from their engine?

Nvidia is not lying about anything, their slide even says it : G-buffer for primary visibility (rasterized) then all light sampling and bounces are ray traced. Go look what a scene looks like with just a G-buffer pre-lighting. Tell me that's the "neat" hack that Nvidia sprinkled on this game to have the look it does. Even the Quake 2 RTX which you can find the path_tracer.h on github, iterates after the G-buffer to replace the surface parameters in the G-buffer afterwards with the surface hit by the bounce ray.

The very definition of using the geometry buffer and to apply textures is.... gasp a rasterized solution.

us and them no GIF by The Orchard Films


Not a single solution out there gets rid of that for gaming, nobody is dumb enough to go that that level or ray tracing when it's already highly efficient, at least not on current hardware.

Him saying that caching invalidates it as path tracing is as fucking dumb as saying that using a denoiser invalidates the solution as path tracing (why not throw MILLIONS of rays for PURE path tracing!)

By the way, go on that very forum and call him out to ask him if Lumen uses RT. Remember that argument?
 
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kingyala

Banned
You quote someone but you still don't understand what you even read

Of course it's not a classic 80's Monte Carlo path tracing like the guy is "confused" about. It's BETTER. Whether you call it path tracing or not, who the fuck cares, that's a debate for scholars, but everyone is refering to Nvidia's solution on their papers as a path tracing solution.

gLq3lvE.jpg


Path tracing is a mean to get to a reference image. There's tons of twists and changes in algorithms since the Monte Carlo solution (which is slow as fuck even by optimization standards nowadays), so is ReSTIR DI + ReSTIR PT a solution towards reference image.

There's not a single pipeline in unreal engine where you're rid of the rasterization either, nor their path tracing plugin. So should epic remove the word path tracing from their engine?

Nvidia is not lying about anything, their slide even says it : G-buffer for primary visibility (rasterized) then all light sampling and bounces are ray traced. Go look what a scene looks like with just a G-buffer pre-lighting. Tell me that's the "neat" hack that Nvidia sprinkled on this game to have the look it does. Even the Quake 2 RTX which you can find the path_tracer.h on github, iterates after the G-buffer to replace the surface parameters in the G-buffer afterwards with the surface hit by the bounce ray.

The very definition of using the geometry buffer and to apply textures is.... gasp a rasterized solution.

us and them no GIF by The Orchard Films


Not a single solution out there gets rid of that for gaming, nobody is dumb enough to go that that level or ray tracing when it's already highly efficient, at least not on current hardware.

Him saying that caching invalidates it as path tracing is as fucking dumb as saying that using a denoiser invalidates the solution as path tracing (why not throw MILLIONS of rays for PURE path tracing!)

By the way, go on that very forum and call him out to ask him if Lumen uses RT. Remember that argument?
so your questioning an epic engineer who worked on unreal 5...
 

kingyala

Banned
Are you for real..? He's clearly stating he doesn't know and that he's making a notion. Why are you so desperate to latch on, it's absurd.
hes an epic engineer who worked on unreal 5 and if he is skeptical i think you should too... instead of jumping on the hype train like some occultists... the renderer is obviously still using a raster pipeline.. the primary visibility or isnt pathtraced...
 
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